Jordin Sparks, the winner of American Idol 6, will be joining Britney Spears' "Circus" tour starting August 24 as the second leg of the tour kicks off in Madison Square Garden. The U.S. leg of the tour wraps September 27 at the NV Mandalay Bay Events Center in Las Vegas.

The show also features Kristinia DeBarge, and in some cities, Girlicious and One Call.

Jordin spent the first part of the summer touring with the Jonas Brothers. Her appearance with pop music's "bad girl" should bolster sales of Jordin's second album, Battlefield, which was released three weeks ago. Sales for the album have been slow, and to date, it's only racked up 77,000 units sold. Jordin's first album sold 119, 000 copies its first week and went on to total two million copies worldwide.